Why talk about 'test printing' when we're still such a long way from finishing the carving? Shouldn't we finish carving the colour blocks before doing any printing?

Good questions ... and yes, basically correct. Test printing of the final version of the print will of course have to wait until all the blocks have been carved. But before we can start carving those colour blocks, we must take some 'proof' impressions from the key block. These proof copies will serve as guides for carving the colour blocks, in much the same way that our original tracing showed us where to carve the key block.

So put aside the carving tools for a while, and let's take some proof impressions from our freshly carved key block ...

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